Fabrication of thin-film transistors based on CdTe/CdHgTe core-shell nanocrystals

Electrical characteristics of field-effect thin-film transistors (TFTs) with p-channels composed of CdTe/CdHgTe core-shell nanocrystals are investigated in this work. For the fabrication of bottom- and top-gate TFTs, CdTe/CdHgTe core-shell nanocrystals synthesized by the colloidal method are first dispersed on oxidized p(+) Si substrates by spin-coating, the dispersed nanocrystals are sintered at 150 degrees C to form the channels for the TFTs, and Al2O3 layers are deposited on the channels. A representative bottom-gate field-effect TFT with a bottom-gate SiO2 layer exhibits a mobility of 0.21 cm(2)/V s and an I-on/I-off ratio of 1.5 x 10(2), and a representative top-gate field-effect TFT with a top-gate Al2O3 layer provides a field-effect mobility of 0.026 cm(2)/V s and an I-on/I-off ratio of 2.5 x 10(2). The CdTe/CdHgTe nanocrystal-based TFTs with bottom- and top-gate geometries are compared in this paper. (c) 2007 Elsevier B.V. All rights reserved.